Method and apparatus for introducing weft threads in weaving machines



March 3, 1970 I v. LUTZE 3,498,333,

' METHOD AND APPARATUS FOR INTRODUCING WEF'I THREADS IN WEAVING MACHINESFiled Jan. 23, 1968 3 Sheets-Sheet l INVEN TOR 501mb LUTZE v. LUTZE ,4METHOD AND APPARATUS FOR INTRODUCING EFT March 3,1970

THREADS IN WEAVING MACHINES s Sheets-Sheet? Filed Jan. 23, 1968 iiiiimllllilll wan VO/kr L 0725 KM-1M March 3, 1970 v. LUTZE 3 METHOD ANDAPPARATUS FOR INTRODUCING WEFT THREADS IN WEAVING MACBINES 5Sheets-Sheet 5 Filed Jan. 23, 1968 F164? v a 14 14'.

u I fa 7K 1s 1s 17 w Emlum by DIRILUTZE United States Patent US. Cl.139-126 Claims ABSTRACT OF THE DISCLOSURE A method and device forinserting weft threads by means of a reciprocating shuttle. The startingends of threads wound on a pair of spools on each side of a warp areheld by suction in a position exteriorly of the path of travel of theshuttle and are brought in timed relationship to the reciprocation ofthe shuttle into another position. In this position one thread is takenalong by the shuttle and inserted in the warp of the fabric. The threadis then trimmed. During the return flight of the shuttle the otherstarting end of the thread is taken along in an opposite direction,inserted in the warp and trimmed.

This invention relates to a method and a device for inserting weftthreads in weaving machines by means of a reciprocating shuttle whichdraws the weft thread from a pair of stationary arranged spools on bothsides of the machine.

In customary machines for weaving the spools of yarn are accommodated inthe weft shuttle. This requires relatively small spools of correspondingsmall capacities.

In order to achieve substantial weaving loads with such machines, theremust be provided spool change mechanisms of expensive construction,which however accomplish their purposes only when thin or mediumthicknesses of yarn are used. On the other hand, when thick yarn isemployed, it is no longer possible to achieve satisfactory loads sincein such cases it is necessary to frequently reload the magazine of thespool change mechanism.

As an innovation, there have also been developed weaving machines whichdraw the weft thread and insert it by means of shuttles, rods or plasticbands from spools arranged externally of the machine. Since in this casethe yarn mechanism is not limited as to size, it is also possible toachieve good performances when using thick yarn.

The invention relates to weaving machines of the above type. The objectof the invention is to provide a method and a device for inserting theweft thread which will make it possible to achieve high performanceswith thick yarn in conventional weaving machines, through inexpensiveconstruction and thus in an economical manner.

According to the method of the invention, the starting end of each yarnwhich is to be inserted, is held by suction in a position exteriorly ofthe path of travel of the shuttle and is brought or fed, in timedrelationship to the reciprocation of the shuttle, into another position.In this other position it is under the influence of a suction forcewhich is arranged in the path of travel of the shuttle member and canthus be taken along by the shuttle for insertion of the yarn. Thus,after the yarn has been inserted, it is separated at its end and the newstarting end is held by suction in a position exteriorly of the path oftravel of the shuttle until the following yarn is inserted by thereturning shuttle.

After the ensuing insertion and while the shuttle is moving further inthe direction of the insertion, the starting end of the inserted yarn isreleased by the shuttle 3,498,338 Patented Mar. 3, 1970 at a point whichis in the suction zone of that suction device which holds the startingend of the yarn which is to be inserted during the following returnmovement of the shuttle, in the position exteriorly of the shuttles pathof travel. The transfer of the starting end of the yarn from theposition in which it is disposed exteriorly of the path of travel of theshuttle, to the position re quired for taking it along, may be effectedby controlling the suction device and/ or by a stream of air. On theother hand, a mechanical adjustable device could be employed for thispurpose, said device being reciprocable in timed relationship to themovement of the shuttle.

Conventional Weaving machines may be employed to carry out the methodaccording to the invention. These can be adapted for this purpose at aslight cost. To accomplish this purpose, according to the invention,suction devices are arranged in the area of the path of travel of theshuttle and spaced therefrom. One of these suction devices holds thestarting end of the yarn thread at a point outside of the path of travelof the shuttle, while the other suction device holds thev starting endof the yarn thread in a position where it can be taken along. In orderto transfer the starting end of the yarn from the former position to thelatter, there is provided a displaceable device which is controlledaccording to the rhythm of the reciprocating movement of the shuttle;advantageously this could be a mechanical device. In order to take alongthe starting end of the yarn to insert it, the shuttle may be providedwith a gripping device or the like.

The suction device which holds the starting end outside of the path ofthe shuttles path of movement is appropriately arranged above said path,while the suction device which holds the starting end of the thread inthe insertion position is arranged directly under the path of travel ofthe shuttle member. Suction tubes, suction scoops or the like can beused and their suction openings may be arranged in the path of movementof the shuttle. To separate the weft thread, after each insertion, fromthe spool of yarn, there may be advantageously provided cutting levers,rotary knives or the like which may be arranged directly near thesuction devices which hold the starting end of the thread outside thepath of travel of the shuttle member.

According to a further feature of the invention, there are arranged, inthe thread feeds, brake devices which hold the threads tight.

According to the invention, a shuttle provided with clamping members orthe like is provided for inserting the weft thread. The clamping membersclamp the starting end of weft thread and are releasable by means ofstops such as rollers disposed in the path of the movement of theshuttle, whereby the thread is freed after the weft thread has beeninserted. The clamping members comprise spring-tensioned clampingelements, which extend into slots arranged in the shuttle, thus formingclamping slots.

The method and device, according to the invention, will be explainedbelow according to the drawing illustrating, by way of example, anembodiment of the invention.

In the drawing:

FIG. 1 is a shuttle shown in top plan view;

FIG. 2 is a schematic elevational view of the inserting device;

FIG. 3 is a time diagram of the individual steps of the method, and

FIGS. 4A-4F consists of schematic illustrations of the steps used in theinsertion of the weft threads.

Referring now to the drawing in detail, the shuttle 1, shown in FIG. 1is symmetric to its central plane. The shuttle is provided with a pairof clamping levers 2 and 2', which are pivoted about shafts 3 and 3'.Springs 4, 4' press against one arm of each of the levers, thus pressingthe other arms against the movable plate 5 which is secured to the lowerside of the shuttle housing in such a manner as to form slots 6, '6'open at the front. The weft threads 7, 7' are inserted into these slotsand are clamped by the clamping levers 8, 8 in these slots so that theycan be carried along 'by the shuttle.

Both levers 2 and 2' have rounded control surfaces 9 and 9 on theirother arms and extend past the longitudinal edges of the shuttle housingand can thus come in contact with control rollers 18, 18' (FIG. 2). Therollers swing the levers against the springs tension, thus opening theslots 6, 6' for freeing the weft thread.

FIG. 2 illustrates schematically the entire arrangement of the weftinserting device. The reed member of the machine is indicated by R. Yarnspools 10, 10" are arranged at both sides near the material ledges andWeft thread 7, 7' is drawn therefrom according to requirements. The weftthreads are carried through thread guide tubes 11, 11' provided withentrance cones which are further made with inlet and outlet lobes whichserve to hold the thread tight when it is pulled in.

Between the reed member R and the spring brakes 12, 12', above thetravel path of the shuttle 1, indicated by the dotted line P, there aredisposed suction scoops 14,

14'. Laterally of these scoops there are provided cutting devices 15,15'. There is further provided, between the spring 'brake and thesuction scoops 14, 14', a fork shaped thread adjusting device 16, 16which is displaceable in the direction of the arrow S. The threads 7 and7' are tensioned under the fork.

Arranged laterally under the suction scoops 14, 14 are suction scoops17, 17 whose suction openings lie under the path of travel P of theshuttle. Near each of these suction scoops there are arranged rollers18, 18' rotatable about a vertical shaft which cooperate with thecontrol surfaces 9, 9 of the swinging levers of the shuttle.

The reciprocating movement of the shuttle takes place in an usualmanner, by means of striker rods 19, 19 and actuators 20, 20'.

In FIG. 2 there are shown, in extended solid lines, the position I, 1 ofthe weft threads 7, 7', in which the starting ends 7a, 7b of both weftthreads are positioned under the effect of the suction scoops 14, 14'.In this position the starting ends are outside of the path of movementof the shuttle 1.

The ready position in which the starting ends 7a, 7b are under theinfluence of the lower scoops 17, 17', is indicated in dotted lines andshown as II and II. In this position the threads lie in the path ofmovement of the shuttle, so that during the passage of the latter theyextend into the slots 6, 6 of the shuttle. The thread is securelyclamped, according to its thickness in the clamp opening (FIG. 1)between the points 21, 21' and the points 22, 22 respectively, so thatit is taken along by the shuttle 1 and drawn into the Weave.

The course of the operation is as follows:

During the movement of the shuttle 1 in the direction of the arrow T,the starting end of the thread 7 of spool 10 is under the influence ofthe suction scoop 14 exteriorly of the path of travel of the shuttle.Before the shuttle changes its direction of movement and has reached thezone of the suction scoop 17, while moving in the direction of the arrowT, the starting end 7a is brought into the suction zone of the suctionscoop 17, i.e. into the ready position II, by the downward movement ofthe fork 16. The starting end of the thread 7a therefore enters into theclamping slot 6', as the shuttle passes by, and is clamped in the clampopening, so that it is carried along by the shuttle moving in thedirection of arrow T, for insertion. As the shuttle flies by under thesuction scoop 14' during this step, the control face 9 of the leverstrikes the roller 18 and the lever 2' is lifted, thereby releasing thethread 7. The starting end of the thread thereby reaches into thesuction zone of the suction scoop 14 and is held securely in the latter,while the shuttle 1 flies further, to be lodged in the actuator 20'. Thelever 2' remains in a raised position during this further flight of theshuttle since the curved control face 9' is emplaced on the wall of thehousing (not shown), said wall preventing the return position of thelever. Finally the yarn thread 7 is separated by the cutting device 15in such a manner that the starting end of the thread extends into thesuction scoop 14 (position 1).

The final weft insertion in the direction of arrow T followsappropriately in the same manner, whereby the thread 7' is drawn intothe clamping slit 8 (FIG. 1) and the clamping is released by means ofthe roller 18, after the ensuing insertion of the weft thread.

FIGS. 3 and 4A-4F illustrate the timing control of the individual steps.FIG. 3 shows a time diagram in which the first crankshaft revolution(1st revolution) during the insertion of the weft b is rendered in theform of a circle which is divided by numerals 31 to 42, while the secondcrankshaft revolution (2nd revolution) corresponding to the insertion ofthe following weft c is represented by a concentric inner circle whichis divided by means of numerals 31' to 42.

The following operational steps correspond to the individual points ofthe diagram:

32.5-The left cutting device 15 cuts off the piece of thread 23 in thesuction scoop 14 from the weft a at the starting end 7b; the short restof the weft 23 is drawn off. The right cutting device 15' separates Wefta into a thread end of the weft a and the new starting end 7b of weft c.The starting end of thread 7b of weft c moves into the position I, i.e.it is aspirated by scoop 14 (FIG. 4B).

33Stroke of weft a through the reed at the edge of the fabric. The leftfork 16 has arrived at the dead point and has thereby brought thestarting end of the thread 7a of weft b into the suction zone of thesuction device 17; the starting end 7a is in the ready position II; itcan be taken over by the shuttle member 1.

34.5The left fork 16 has again moved upward.

35Introduction on the left for the flight of the shuttle member 1 fromleft to right (arrow direction T). During the initial acceleration ofthe shuttle member 1 the starting end 7a of weft b enters the slot 6' ofthe shuttle.

36The starting end 7a of weft b is clamped securely, depending on itsthickness, between the points 22' and 21', in the shuttle. The weftthread b is taken along, i.e. the weft b is pulled in (FIG. 4C).

36-4l-The shuttle member 1 flies through the compartment from left toright.

40.5-Roller 18 on the machine opens the clamping position 8'; thesuction scoop 14' aspirates the freed starting end 7a of the weft b.

31.5 (2nd revolution)Right fork 16' begins to move downward (arrow S).

32.5The right cutting device 15 cuts off the thread piece in the suctionscoop 14 from the weft b at the starting end 7a; the short rest of theWeft 23 is aspirated. The left cutting device 15 separates weft b whileforming the new starting end of the thread 7a. The starting end 7a ofweft d moves into the position I, i.e. it is aspirated by the suctionscoop 14 (FIG. 4D).

33'Impact of weft b against the fabrics edge. The fork 16' has movedinto the lower dead point and has thereby carried the starting end 7b ofweft c into the suction zone of the suction scoop 17; the starting end7b is in the ready position 11' and can be taken over by the shuttlemember 1. 34.5The right fork 16 has moved upwards again. 35'-Insertionfor the flight of the shuttle member from right to left (arrow T). Thestarting end 7b of weft c enters the slot 6 of the shuttle member 1.46The starting end 7b of the weft c is clamped, ac-

cording to its thickness, between the points 22 and 21 in the shuttlemember. The weft thread 0 is taken along, i.e. the weft c is drawn in(FIG. 4E). 36'41'The shuttle member flies through the compartment fromright to left (arrow T). 40.5'Roller 18, on the left side of themachine, opens the clamping position 8; the suction scoop 14 aspiratesthe released starting end of the thread 7', of the weft c.

FIG. 4F illustrates the further steps until the stopping of the weft c,i.e. the cutting device 15 separates the remainder of the weft in thesuction scoop 14 and the cutting device 15' separates the weft c. Thefork 16 has moved downwards in the direction of the arrow S and hasbrought the starting end 70' of the thread into the suction zone of thesuction scoop 17.

The rapport of the movement including two compartment openings, apassage from left to right, a passage from right to left and two stopsis thus completed.

I claim:

1. The method of inserting weft thread in the warp of a fabric to bewoven from opposite sides of a warp, comprising arranging a pair ofstarting ends of weft threads in a horizontal upper path at stations oneach side of a fabric warp, deflecting one weft thread end downward,conducting the one weft thread in a horizontal lower path in onedirection, inserting the one weft thread in the warp; following theinsertion of the one end of the weft thread, deflecting the starting endof the second weft thread downward, conducting said second weft threadin a horizontal lower path in an opposite direction from said onedirection to the other side of the fabric warp, inserting the secondthread in the fabric warp, aspiring the terminal portions of thestarting ends of the weft threads, securing the starting ends of thethreads while in said upper path, aspirating the terminal portions ofthe starting ends while thus secured, after said ends have beendeflected downward, arresting the travel of each of the weft threads ata predetermined point and cutting off the remainder of each said warp atthe respective warp.

2. In a weaving machine arranged for moving a warp for a fabric in ahorizontal plane, a pair of spools of thread spacedly disposed on eachside of the warp, means for holding the starting ends of the thread inan upper horizontal path transverse to the warp, a shuttle reciprocatingthrough the warp in a lower path parallel to said upper path, saidshuttle having clamping means for clamping said ends, means forimparting reciprocal movement to said shuttle, means for downwardlydeflecting the starting ends of the thread in the path of said shuttle,means for holding said ends in the downwardly deflected position, meansfor interrupting the movement of the shuttle after its passage throughthe warp in one direction, means for interrupting the movement of theshuttle after its passage through the Warp in an opposite direction andcutting means for severing remainder of the thread after the respectivepassages.

-3. In a weaving machine as claimed in claim 2, said means for holdingthe starting ends of the thread in said upper path being arranged abovesaid lower path, said means for holding the starting end in thedownwardly deflected position being arranged below said lower path.

4. In a weaving machine as claimed in claim 3, said holding meansconsisting of suction scoops.

5. In a weaving machine as claimed in claim 4, said means for downwardlydeflecting the starting ends 0 fthe thread being formed as verticallydisplaceable fork members.

6. In a weaving machine as claimed in claim 5, brake means arranged insaid upper path, for holding the starting ends of said threads.

7. In a weaving machine as claimed in claim 6, said clamping means insaid shuttle comprising a pair of twoarmed clamping levers pivotablymounted in said shuttle, a movable plate in said shuttle, the lower endsof said levers protruding downwardly of said shuttle, and spring meansfor biasing the upper ends of said levers against said movable plate forengaging said starting ends of the thread therebetween.

'8. In a weaving machine as claimed in claim 7, said means forinterrupting the movement of the shuttle consisting of a pair of rollersmounted for vertical axial rotation in said lower path of the shuttle.

9. In a weaving machine as claimed in claim 8, said cutting means beingarranged intermediate said rollers and the warp.

10. In a weaving machine as claimed in claim 9, said means for impartingmovement to the shuttle consisting of a pair of striker rods andactuators secured to said rods.

References Cited UNITED STATES PATENTS 1,632,912 6/1927 Mullor et al.139125 1,729,413 9/1929 Ashton 139125 2,946,353 7/1960 Dunham 139-1253,213,892 10/1965 Fluhmann 139126 3,299,912 1/ 1967 Birmans et al.139-194 3,310,073 3/1967 Claeys 139-126 X 3,378,040 4/1968 Moessinger139122 FOREIGN PATENTS 1,327,504 4/ 1963 France.

386,941 4/1965 Switzerland.

JAMES KEE CHI, Primary Examiner US. Cl. X.R. 139-494

